Some time ago I started on a mobile version of a desktop game released under GPLv2. At first, the desktop version was just inspiration, but I've reached the point where I suck as an artist and would like to just re-use the artwork in my game. Would doing so mean my game has to be released under the GPL? I am not modifying the artwork or any of the code; I am not even re-using the code. I'm just using the artwork, and some text files that describe game levels.

The GPL-2.0 license is intended for source code. Can you confirm that the assets are in-fact licensed in this manner? Typically, projects of this nature license their assets under a Creative Commons license. Additionally, it would be helpful if you could provide a link to the desktop game in question.
– rageAug 15 '19 at 12:02

@LucasRamage I added a link to the game in question.
– Jeff BargerAug 16 '19 at 1:53

2 Answers
2

With respect to my colleague, Doc Brown, I disagree. Some of the only jurisprudence we have about using artwork under a copyleft licence as part of a greater work comes from Drauglis v. Kappa Map Group. Although the copyleft content in Drauglis was under CC-BY-SA, not GPL, I believe the analysis applies because the question of what constitutes a derivative is a copyright question, not a licence-specific one.

In this case, the court found that not only was the whole work (a road atlas) not a derivative of the CC-BY-SA cover photo, even the cover image was only a collective work, not a derivative one.

Though that case isn't a binding authority in any jurisdiction, given that you're not modifying the artwork the analysis seems germane, and suggests that you could use the artwork taken from the GPL source game without having to GPL your entire game. You would need to honour the terms of the GPL with respect to the artwork, though. And, of course, IANAL/IANYL, so you would do well to take qualified legal advice before relying heavily on this.

Though the GPL surely was intended for "usual source code", it applies AFAIK to images and artwork as well. Especially in the described case, some images of the original game are in SVG format, which is just an XML format, which can clearly be seen as a form of "source code" (but beware, what I wrote applies also to pictures in binary format like JPEG or PNG).

So yes, if you want to use the images in your game, you need to follow the GPL license, which means as soon as you release it to the world, you need to put it under GPL as well. If you don't like this, better ask the authors if they give you a permission for using a different license.

A similar question was asked formely on law.SE, and the answers seem to confirm this.